The present invention relates generally to improvements in microfilm readers and it relates more particularly to an improved cursor mechanism for facilitating the reading of successive parallel lines of an image projected on a microfilm reader screen even where these lines are not precisely laterial.
The convention cursor mechanism associated with a microfilm reader generally includes a vertically adjustable cursor bar which is angularly fixed so as to be laterally horizontal so that when it is vertically moved it is always horizontal and parallel to itself. While such a cursor mechanism is highly satisfactory where the lines of the image projected on the viewing screen, for example, lines of typography are always precisely horizontal and parallel to the upper and lower edges of the viewing screen, such a mechanism is unsuitable and less than satisfactory when applied to viewed images whose parallel lines are inclined to the horizontal. Since it frequently occurs that the lines of a projected image are inclined to the horizontal, for example, in the case where the film itself is projected in an inclined manner or the photographed original is inclined, the conventional cursor mechanism leaves much to be desired since it fails to align with the image lines in many cases and hence fails to achieve its proper and intended function.